Water Chemistry

[pmb_67]

Just had some pretty shocking results with a few water test kits... been using them for a while to monitor my tank, but found even 20-25% weekly water changes won't get the nitrate below the middle of the scale (25mg/l) on the Tetra NO3 kit, while phosphate is at 2mg/l (the next-to-highest reading on a Hagen/Nutrafin kit). Only ever tested the tap water for general hardness and pH, and at dH 20 and pH8 got a pretty good clue as to why the tank is dH18 and pH8. Tank hardness did get as low as dH16 a while back, though this was during an outbreak of small snails so I reckon maybe they used up some of the calcium. Please feel free to laugh uncontrollably at this theory...

Anyway, I tested my (London) tap water today and was shocked to find phosphate is over 5mg/l - off the scale of the test kit. No wonder the tank's level isn't coming down (and the algae - and plants - are doing well). Nitrate is also non-zero, in the 12.5 mg/l zone - again, pretty much explains why I can't get the tank concentration down, the little fellas have gotta eat... (and yes, I try not to overfeed). Ammonia also tested high - 1.5mg/l (middle of the Tetra kit scale), but I figure this is the chloramine that Thames Water are helpfully chucking in there...

So, finally my question - how do I get good water for my tank? I'm in a flat so can't collect rainwater (read in PFK that this can be quite good if done properly), don't have a car so can't be trekking to the LFS for some RO water every week, so what are my options? I have two filters on the tank, a Fluval 2+ internal and a box that sits in the hood (came with tank), so I can stick PO4 adsorber in there if necessary - but I'm thinking it would be better not to add it in the first place.

According to my LFS (and books) the ideal water chemistry for my gang of critters is pH7, dH10 so any comments on getting to that also welcome; OTOH everyone seems pretty happy with the stats as they are so I'm not desperate to perfect them. Longer term plan is get a 2nd tank, put the tetras (and a few other guests) in one and give 'em some nice soft acidic water...

All suggestions welcome, including pointing me to someplace where this thread already exists!

Thanks,

Paul

Tank: 70 litre, 25C, zero NH3, zero NO2, 25mg/l NO3, dH18, pH8, 5mg/l PO4, 5mg/l dissolved O2 - been running since May, pretty stable other than a platy-loss incident a few weeks back

Fish: 1 variegated platy (male), 2 guppies (male), 5 neons (?), 4 glowlights (?), 3 longfin leopard danios (1M 2F)

 

[Bloo]

to TFF !

You have many questions I see - perhaps not best answered in this section where few people pass by. You will be better off in the beginners section, chit chat or even the planted section

However.... fist of all to put your mind at ease - I live in London too and am supplied by Thames Water. Have you received a report from them ?

I find it confusing that you say you have no nitrates - when the tapwater contains an average of 35ppm. So a tank with fish could very easily push that to 50ppm. Unless you have a massively planted tank

If you look at my profile info, you will see the combo of fish I healthily keep in the same water.
You will also find that the tapwater pH will swing between 7.6 and up to 8.4 at times.

Fish I have not been able to keep in this water, are Rams & Neons - so I suggest you stay away from fish that require very soft and acidic water.

Have a look at this article on pH, kH & gH to give you a better understanding of your water.

As you have Ammonia, your tank is still going through a cycle - and to understand the Nitrogen Cycle, have a look at this article.

Whatever you do, do not add chemicals other than dechlorinator to your water. Do not fiddle with pH adjusters and NO3 removers etc. etc.

And unless you go the RO water route (expensive and time consuming) you will have to make do with the tapwater you have

Hope that helps. Feel free to ask any further questions

 

[pmb_67]

to TFF !

You have many questions I see - perhaps not best answered in this section where few people pass by. You will be better off in the beginners section, chit chat or even the planted section

However.... fist of all to put your mind at ease - I live in London too and am supplied by Thames Water. Have you received a report from them ?

I find it confusing that you say you have no nitrates - when the tapwater contains an average of 35ppm. So a tank with fish could very easily push that to 50ppm. Unless you have a massively planted tank

If you look at my profile info, you will see the combo of fish I healthily keep in the same water.
You will also find that the tapwater pH will swing between 7.6 and up to 8.4 at times.

Fish I have not been able to keep in this water, are Rams & Neons - so I suggest you stay away from fish that require very soft and acidic water.

Have a look at this article on pH, kH & gH to give you a better understanding of your water.

As you have Ammonia, your tank is still going through a cycle - and to understand the Nitrogen Cycle, have a look at this article.

Whatever you do, do not add chemicals other than dechlorinator to your water. Do not fiddle with pH adjusters and NO3 removers etc. etc.

And unless you go the RO water route (expensive and time consuming) you will have to make do with the tapwater you have

Hope that helps. Feel free to ask any further questions

Thanks for the feedback, bloozoo2.

I'm with you on the adding as few chemicals as possible to the tank - that's why I was wondering about getting the water nice and ion-free before putting it in )

One thing on the nitrate and ammonia - as I wrote above, ammonia (NH3, or NH4+ in ionic form) is definitely a big fat zero, while the nitrates are up at 25mg/l (sorry, don't know the ppm equivalent); I took it nice and steady when I set up back in May, did a fish-free cycle then added the fish in small batches - none added for some time now and everything is fine and dandy. Apart from the PO4/NO3 issue...

Any more tips always welcome )

 

[Bloo]

Ahh I'm with you now. Cool, you have a fully cycled tank doing well by the sounds of it. Apart form the PO4 - if this is causing a problem, you need to swing by the planted section if you have algae ridden live plants.
There are loads of great pinned topics there - one of which is, zig's Estimative Index Article, say "goodbye" to algae forever Options . Another being Algae in the Planted Aquarium.

HTH